Abstract:
The tension lifter of cam chain in 4-stroke motorcycle engine obtains both the tensile force and compressive force due to the flap of cam chain. Both tensile and compress loads are called the fluctuating load. After some mileages, the fatigue occurred in spiral spring which affected to the tension of cam chain, abnormal noise, and engine damage.
In this study, the tension lifters of cam chain, which has already been used between 0 to 30,000 kilometers, were tested by cam chain tester and vibration tester. The results show that the distance between 0 - 5,000 kilometer, has the best compressive resistance time which is 20.16 second of the testing time. The testing was done continuously, the compressive resistance had reduced to 12.67 second at 30,000 kilometer. It dropped down to 58% when compared to 0 kilometer. The Ansys program gave the analysis result where the maximum stress occurred on the spiral spring, then the absorber was attached. After 120 minutes of the testing time, the results shown the strain decreased to 0.005 micro strain compared to the part without absorber.
This procedure decreases the strain occurred on spiral spring that caused by fatigue. Also, it increases the compressive resistance of the tension lifter and the engine noise has consequently reduced after applied the absorber.